Refactor fido.py moving CLI argument parsing into its own `cli_args…

….py`. Add some tests to the argument parsing.

Add the CONFIG_DIR to the dictionary of defaults in fido.py.

fido/cli_args.py

@@ -3,11 +3,15 @@
 from argparse import ArgumentParser, RawTextHelpFormatter
 
 
-def build_parser() -> ArgumentParser:
-    defaults = {
-        "description": "FIDO - File Identification Tool",
-        "epilog": "For more information, visit the official documentation.",
-    }
+def parse_cli_args(argv: list[str], defaults: dict) -> argparse.Namespace:
+    """
+    Parse command-line arguments.
+    Args:
+        argv (list[str]): List of command-line arguments. Could be sys.argv
+        defaults (dict): Dictionary of default values. Expects to find configdir, bufsize and container_bufsize.
+    Returns:
+        argparse.Namespace: Parsed command-line arguments. Reference via name as in args.v or args.recurse.
+    """
 
     parser = ArgumentParser(
         description=defaults["description"],
@@ -63,16 +67,43 @@ def build_parser() -> ArgumentParser:
         default=None,
         help="comma separated string of formats not to use in identification",
     )
+    parser.add_argument(
+        "-matchprintf",
+        metavar="FORMATSTRING",
+        default=None,
+        help="format string (Python style) to use on match. See nomatchprintf, README.txt.",
+    )
+    parser.add_argument(
+        "-nomatchprintf",
+        metavar="FORMATSTRING",
+        default=None,
+        help="format string (Python style) to use if no match. See README.txt",
+    )
+    parser.add_argument(
+        "-bufsize",
+        type=int,
+        default=None,
+        help=f"size (in bytes) of the buffer to match against (default={defaults['bufsize']})",
+    )
+    parser.add_argument(
+        "-sigs",
+        default=None,
+        metavar="SIG_ACT",
+        help='SIG_ACT "check" for new version\nSIG_ACT "update" to latest\nSIG_ACT "list" available versions\nSIG_ACT "n" use version n.',
+    )
+    parser.add_argument(
+        "-container_bufsize",
+        type=int,
+        default=None,
+        help=f"size (in bytes) of the buffer to match against (default={defaults['container_bufsize']}).",
+    )
+    parser.add_argument(
+        "-loadformats", default=None, metavar="XML1,...,XMLn", help="comma separated string of XML format files to add."
+    )
+    parser.add_argument(
+        "-confdir",
+        default=defaults["config_dir"],
+        help="configuration directory to load_fido_xml, for example, the format specifications from.",
+    )
 
-    return parser
-
-
-def parse_args(parser: ArgumentParser) -> argparse.Namespace:
-    try:
-        args = parser.parse_args()
-    except argparse.ArgumentError as e:
-        parser.print_help()
-        print(f"\nError: {e}\n")
-        sys.exit(1)
-
-    return args
+    return parser.parse_args(argv)

fido/fido.py

@@ -13,23 +13,20 @@
 import sys
 import tarfile
 import tempfile
-from argparse import ArgumentParser, RawTextHelpFormatter
-from contextlib import closing
-
-try:
-    from time import perf_counter
-except ImportError:
-    from time import clock as perf_counter
-
 import zipfile
+from contextlib import closing
+from time import perf_counter
+from typing import Optional
 from xml.etree import cElementTree as ET
 
 from fido import CONFIG_DIR, __version__
 from fido.char_handler import escape
+from fido.cli_args import parse_cli_args
 from fido.package import OlePackage, ZipPackage
 from fido.versions import get_local_versions, sig_file_actions
 
 defaults = {
+    "config_dir": CONFIG_DIR,
     "bufsize": 128 * 1024,  # (bytes)
     "regexcachesize": 2084,  # (bytes)
     "printmatch": 'OK,%(info.time)s,%(info.puid)s,"%(info.formatname)s","%(info.signaturename)s",%(info.filesize)s,"%(info.filename)s","%(info.mimetype)s","%(info.matchtype)s"\n',
@@ -74,8 +71,8 @@ class Fido:
 
     def __init__(
         self,
-        quiet=False,
-        bufsize=None,
+        quiet: bool = False,
+        bufsize: Optional[int] = None,
         container_bufsize=None,
         printnomatch=None,
         printmatch=None,
@@ -793,107 +790,7 @@ def main(args=None):
     """Main FIDO method."""
     if not args:
         args = sys.argv[1:]
-
-    parser = ArgumentParser(
-        description=defaults["description"],
-        epilog=defaults["epilog"],
-        fromfile_prefix_chars="@",
-        formatter_class=RawTextHelpFormatter,
-    )
-    parser.add_argument("-v", default=False, action="store_true", help="show version information")
-    parser.add_argument("-q", default=False, action="store_true", help="run (more) quietly")
-    parser.add_argument("-recurse", default=False, action="store_true", help="recurse into subdirectories")
-    parser.add_argument("-zip", default=False, action="store_true", help="recurse into zip and tar files")
-    parser.add_argument(
-        "-noextension",
-        default=False,
-        action="store_true",
-        help="disable extension matching, reduces number of matches but may reduce false positives",
-    )
-    parser.add_argument(
-        "-nocontainer",
-        default=False,
-        action="store_true",
-        help="disable deep scan of container documents, increases speed but may reduce accuracy with big files",
-    )
-    parser.add_argument(
-        "-pronom_only",
-        default=False,
-        action="store_true",
-        help="disables loading of format extensions file, only PRONOM signatures are loaded, may reduce accuracy of results",
-    )
-
-    group = parser.add_mutually_exclusive_group()
-    group.add_argument(
-        "-input", default=False, help="file containing a list of files to check, one per line. - means stdin"
-    )
-    group.add_argument(
-        "files",
-        nargs="*",
-        default=[],
-        metavar="FILE",
-        help="files to check. If the file is -, then read content from stdin. In this case, python must be invoked with -u or it may convert the line terminators.",
-    )
-
-    parser.add_argument("-filename", default=None, help="filename if file contents passed through STDIN")
-    parser.add_argument(
-        "-useformats",
-        metavar="INCLUDEPUIDS",
-        default=None,
-        help="comma separated string of formats to use in identification",
-    )
-    parser.add_argument(
-        "-nouseformats",
-        metavar="EXCLUDEPUIDS",
-        default=None,
-        help="comma separated string of formats not to use in identification",
-    )
-    parser.add_argument(
-        "-matchprintf",
-        metavar="FORMATSTRING",
-        default=None,
-        help="format string (Python style) to use on match. See nomatchprintf, README.txt.",
-    )
-    parser.add_argument(
-        "-nomatchprintf",
-        metavar="FORMATSTRING",
-        default=None,
-        help="format string (Python style) to use if no match. See README.txt",
-    )
-    parser.add_argument(
-        "-bufsize",
-        type=int,
-        default=None,
-        help="size (in bytes) of the buffer to match against (default=" + str(defaults["bufsize"]) + " bytes)",
-    )
-    parser.add_argument(
-        "-sigs",
-        default=None,
-        metavar="SIG_ACT",
-        help='SIG_ACT "check" for new version\nSIG_ACT "update" to latest\nSIG_ACT "list" available versions\nSIG_ACT "n" use version n.',
-    )
-    parser.add_argument(
-        "-container_bufsize",
-        type=int,
-        default=None,
-        help="size (in bytes) of the buffer to match against (default="
-        + str(defaults["container_bufsize"])
-        + " bytes)",
-    )
-    parser.add_argument(
-        "-loadformats", default=None, metavar="XML1,...,XMLn", help="comma separated string of XML format files to add."
-    )
-    parser.add_argument(
-        "-confdir",
-        default=CONFIG_DIR,
-        help="configuration directory to load_fido_xml, for example, the format specifications from.",
-    )
-
-    if len(sys.argv) == 1:
-        parser.print_help()
-        sys.exit(1)
-    args = parser.parse_args(args)
-
+    args = parse_cli_args(args, defaults)
     timer = PerfTimer()
 
     versions = get_local_versions(args.confdir)
@@ -904,15 +801,13 @@ def main(args=None):
     defaults["format_files"] = [defaults["xml_pronomSignature"]]
 
     if args.pronom_only:
-        versionHeader = "FIDO v{0} ({1}, {2})\n".format(
-            __version__, defaults["xml_pronomSignature"], defaults["containersignature_file"]
+        versionHeader = (
+            f"FIDO v{__version__} ({defaults['xml_pronomSignature']}, {defaults['containersignature_file']})\n"
         )
     else:
-        versionHeader = "FIDO v{0} ({1}, {2}, {3})\n".format(
-            __version__,
-            defaults["xml_pronomSignature"],
-            defaults["containersignature_file"],
-            defaults["xml_fidoExtensionSignature"],
+        versionHeader = (
+            f"FIDO v{__version__} ({defaults['xml_pronomSignature']}, {defaults['containersignature_file']}, "
+            f"{defaults['xml_fidoExtensionSignature']})\n"
         )
         defaults["format_files"].append(defaults["xml_fidoExtensionSignature"])
 

tests/test_cli_args.py

@@ -1,61 +1,54 @@
-import argparse
-
 import pytest
 
-from fido.cli_args import build_parser, parse_args
+from fido.cli_args import parse_cli_args
+from fido.fido import defaults
 
 # Common argument string
-ARG_STRING = (
-    "-v -q -recurse -zip -noextension -nocontainer -pronom_only"
-    "-input files.txt"
-    "-useformats=fmt1,fmt2 -nouseformats=fmt3,fmt4"
-)
-
-ARG_STRING = (
-    "-v -q -recurse -zip -noextension -nocontainer -pronom_only"
-    "-input files.txt"
-    "-useformats=fmt1,fmt2 -nouseformats=fmt3,fmt4"
-)
-
-
-def test_build_parser():
-    parser = build_parser()
-    assert isinstance(parser, argparse.ArgumentParser)
-
-    # Check if all expected arguments are present
-    expected_args = ARG_STRING.split()
-    for arg in expected_args:
-        assert arg in parser._option_string_actions
-
-
-def test_parse_args_valid():
-    parser = build_parser()
-
-    args = parse_args(parser.parse_args(ARG_STRING.split()))
-
-    assert args.v is True
-    assert args.q is True
-    assert args.recurse is True
-    assert args.zip is True
-    assert args.noextension is True
-    assert args.nocontainer is True
-    assert args.pronom_only is True
-    assert args.input == "input_file"
-    assert args.files == ["file1", "file2"]
-    assert args.filename == "filename"
+
+
+def test_parse_args_input_valid():
+    arg_string = (
+        "-v -q -recurse -zip -noextension -nocontainer -pronom_only "
+        "-input files.txt "
+        "-useformats=fmt1,fmt2 -nouseformats=fmt3,fmt4"
+    )
+    args = parse_cli_args(arg_string.split(), defaults)
+    print(arg_string.split())
+    print(args)
+    assert args.v
+    assert args.q
+    assert args.recurse
+    assert args.zip
+    assert args.noextension
+    assert args.nocontainer
+    assert args.pronom_only
+    assert args.input == "files.txt"
     assert args.useformats == "fmt1,fmt2"
     assert args.nouseformats == "fmt3,fmt4"
 
 
-def test_parse_args_invalid(monkeypatch):
-    parser = build_parser()
+def test_parse_args_files_valid():
+    arg_string = "-q -zip file1.ext file2.ext"
+    args = parse_cli_args(arg_string.split(), defaults)
+    print(arg_string.split())
+    print(args)
+    assert args.q
+    assert args.zip
+    assert args.noextension == False
+    assert args.nocontainer == False
+    assert args.pronom_only == False
+    assert args.files == ["file1.ext", "file2.ext"]
+    assert args.useformats is None
+    assert args.nouseformats is None
 
-    # Simulate invalid argument input
-    monkeypatch.setattr("sys.argv", ["prog", "--invalid"])
+
+def test_parse_args_invalid():
+    arg_string = "-q -zip -bad_arg file1.ext file2.ext"
     with pytest.raises(SystemExit):
-        parse_args(parser)
+        args = parse_cli_args(arg_string.split(), defaults)
+
 
-    # Simulate missing required argument
-    monkeypatch.setattr("sys.argv", ["prog", "-input"])
+def test_parse_files_and_input_invalid():
+    arg_string = "-q -zip -input files.txt file1.ext file2.ext"
     with pytest.raises(SystemExit):
-        parse_args(parser)
+        args = parse_cli_args(arg_string.split(), defaults)